The association of birth weight and current BMI on the risk of hypertension: the Tohoku medical megabank community-based cohort study

This study aimed to investigate the association of combination of birth weight and current body mass index (BMI) with the risk of hypertension in adulthood. This cross-sectional study used data from the Tohoku Medical Megabank Community-based Cohort Study conducted in Japan. A total of 10,688 subjects aged ≥20 years were eligible. We calculated the least square (LS) means of systolic blood pressure (SBP) and trend tests were performed to evaluate the linear relationships between birth weight categories and SBP. We also used a multivariate logistic regression analysis to assess the risk of hypertension associated with the combination of birth weight and current BMI. There was a statistically inverse association between birth weight and SBP in the 20–64 age group, but no significant association in the ≥65 age group. Low birth weight (LBW) with normal BMI group had a higher risk of hypertension than the normal or high birth weight groups with normal BMI. Furthermore, the group with LBW and BMI ≥25.0 kg/m2 was the highest risk for hypertension (adjusted odds ratio: 2.73; 95% CI, 2.04–3.65) compared to the reference group (birth weight 2500–3499 g and BMI 18.5–24.9 kg/m2). There was a significant association between LBW and subsequent risk of hypertension. In addition, participants with lower birth weights had a higher risk of hypertension than those with higher birth weights. However, even in participants with a lower birth weight, the risk of hypertension could be reduced when they maintained an optimal BMI.